This invention relates generally to a heating system and, more particularly, to a heating system which utilizes an infrared burner module having a heat exchanger coil wrapped around a radiant burner.
In heating systems for homes and commercial buildings, central furnaces to heat a space all operate on the same general principle. Air for a space to be heated circulates around a closed system, and is heated either as it passes through a heat exchanger in contact with a burning fuel, or as it passes in contact with a secondary fluid which has been heated by a burning fuel. Since burning the fuel results in the production of noxious combustion gases having exhaust temperatures which can exceed 500.degree. F., it is necessary to exhaust the combustion gases through a chimney or flue to the atmosphere. These systems are relatively inefficient due to the high exhaust temperatures of the flue gases, and costly due to the construction of the necessary flue or chimney.
An indirect fired furnace, one in which the air being heated is not contacted directly by the combustion gases generated, is generally used in both forced air systems and hydronic systems.
A forced air system consists primarily of a heat exchanger having combustion chambers arranged in relation to the flow of air to be heated such that fuel is introduced at the lower end of the chamber where a combustion flame causes heat to be generated. The heat rises through a series of internal passages before exiting through an upper end of the combustion chamber into the flue or chimney. Simultaneously, circulated space air to be heated passes around the outside of the heat exchangers to absorb heat through conduction and convection.
A hydronic system consists primarily of a firebox having a heat exchanger therein. The heat exchanger is in a closed loop for continuously circulating fluid, e.g. water, from the heat exchanger to a remote radiator located in the space to be heated. However, this system is also relatively inefficient and expensive due to the combustion gas temperatures at the outlet of the firebox, the cost of the chimney, and the delay in heating the mass of liquid in the closed loop.
In an attempt to increase the efficiency of a heating system condensing furnaces were implemented. In condensing furnaces exhaust combustion gases are used to preheat the space air prior to this air contacting the primary heat exchanger. Thus, in this type of furnace exhaust temperatures are reduced but corrosive condensates are formed as the exhaust combustion gases are reduced below their dew point.
Another drawback of known heating systems is the large size of the furnace. The large furnace structure is the result of the need for large heat exchange surface areas to transfer the heat from the combustion products of the ribbon burner to the space air or hydronic fluid.
Still another drawback of known heating systems is the use of only air or water as the heating medium.
Another problem in space heating installations is the annoying low frequency noise called combustion roar caused by products of combustion within the furnace. This is especially true where the furnace is connected to a duct of the heating system which tends to amplify the noise.
Still another problem in previously known heating systems, as a result of the combustion process used in these systems, is that a furnace normally generates gaseous combustion products which include oxides of nitrogen (NO.sub.X) which are vented to the atmosphere as flue gases. It is desirable to limit these oxides of nitrogen emissions since NO.sub.X is considered a pollutant, and combustion systems for gas-fired furnaces sold in certain geographical areas must meet strict NO.sub.X emission standards.
Thus, there is a clear need for a gas heating system having a modular design that will, to a large extent, overcome the problems noted in the prior art.